Armore Indistinguishable from 

 Robinson " " 



Midland " " 



Sparkle " " 



Gem " " 



-6- 

 Red Cluster 



Kardinal King and Scarlet Beauty 



Crimson Flash and Adonis 



Paymaster 



Superfection and Brilliant 



•—James F. Anderson 

 I I I I I I I I I I I I I I I I 



RED STELE; NUMBER ONE MENACE OF THE STRAWBERRY 



Red stele has became the nvmber one enemy of strawberries in the eastern 

 states. It appeared in Massachusetts about 20 years ago. For awhile it spread 

 very slowly but during the past few years it has appeared in many fields, particu- 

 larly in southeastern Massachusetts. 



Red stele is a root disease which has never been found in any other part of 

 the plant. It is caused by a fungus which lives in the soil as well as in the 

 roots of strawberry plants. This fungus forms resting spores which can remain 

 alive in the soil for 18 - 20 years till temperature and moisture conditions 

 are just right and strawberry roots are present. Then these spores germinate 

 and infect the strawberry roots. 



The disease gets its name from the appearance of the roots of infected plants < 

 In spring when the soil is cool and wet the central core or "stele" turns a brick 

 red. This can be observed by stripping off the outer "skin" of the root with 

 the thumbnail or making a slanting cut with a knife. The roots of infected plants 

 fail to branch so that they have a "rat-tail" appearance. The leaves of infected 

 plants wilt. If the infection is not too severe and warm dry weather occurs, 

 the plants may appear to recover but symptcHos are sure to reappear the follow- 

 ing spring when the soil is again cool and wet. If the infection is severe 

 and the soil remains cool and wet, many plants of susceptible varieties may die 

 leaving bare spots in the field. 



Red stele can be spread by infested soil particles clinging to tools and 

 machinery, to the feet of workers, birds or animals, by water-movement through 

 drainage, washing or by irrigation with water contaminated by spores or by 

 setting of infected plants. 



The red stele fungus has a sexual stage and, therefore, occasionally 

 produces mutants, or "sports". As a result there are now five known "races" of 

 red stele. Only four have been found under field conditions. When red stele 

 was first discovered and only one race was known, several strawberry varieties 

 showed considerable resistance. Among these were Aberdeen, Pathfinder, Fair- 

 land, Sparkle, Temple, and Vermilion. Then other races, to which these varieties 

 are not resistant, appeared and decimated these varieties. 



Plant breeders are working to develop varieties resistant to red stele. 

 The first variety resistant to more than one race of red stele was Stelemaster 

 which is resistant to three races. Yield and fruit quality are such that this 



